As this kind of illumination device in the past, there is known one that includes many substrates each mounting a number of white light emission diodes and employs a configuration arranging these many substrates by changing the angles thereof so as to form polygonal planes to emit light in many directions (refer to Patent document 1).
In this illumination device, however, the light is emitted in the upper direction of a main body part. Particularly for a street light and the like, there is a problem that the above light emitted in the upper direction increases the glare to cause light pollution when the device is viewed from above and the light in the upper direction does not contribute to the illumination on a plane to be illuminated to deteriorate illumination efficiency.